"use strict";

// Do this as the first thing so that any code reading it knows the right env.
process.env.BABEL_ENV = "development";
process.env.NODE_ENV = "development";

// Makes the script crash on unhandled rejections instead of silently
// ignoring them. In the future, promise rejections that are not handled will
// terminate the Node.js process with a non-zero exit code.
process.on("unhandledRejection", (err) => {
	throw err;
});

// Ensure environment variables are read.
require("../config/env");

const fs = require("fs");
const chalk = require("react-dev-utils/chalk");
const webpack = require("webpack");
const WebpackDevServer = require("webpack-dev-server");
const clearConsole = require("react-dev-utils/clearConsole");
const checkRequiredFiles = require("react-dev-utils/checkRequiredFiles");
const { choosePort, createCompiler, prepareProxy, prepareUrls } = require("react-dev-utils/WebpackDevServerUtils");
const openBrowser = require("react-dev-utils/openBrowser");
const semver = require("semver");
const paths = require("../config/paths");
const configFactory = require("../config/webpack.config");
const createDevServerConfig = require("../config/webpackDevServer.config");
const getClientEnvironment = require("../config/env");
const react = require(require.resolve("react", { paths: [paths.appPath] }));

const env = getClientEnvironment(paths.publicUrlOrPath.slice(0, -1));
const useYarn = fs.existsSync(paths.yarnLockFile);
const isInteractive = process.stdout.isTTY;

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
	process.exit(1);
}

// Tools like Cloud9 rely on this.
const DEFAULT_PORT = parseInt(process.env.PORT, 10) || 3000;
const HOST = process.env.HOST || "0.0.0.0";

if (process.env.HOST) {
	console.log(
		chalk.cyan(`Attempting to bind to HOST environment variable: ${chalk.yellow(chalk.bold(process.env.HOST))}`)
	);
	console.log(`If this was unintentional, check that you haven't mistakenly set it in your shell.`);
	console.log(`Learn more here: ${chalk.yellow("https://cra.link/advanced-config")}`);
	console.log();
}

// We require that you explicitly set browsers and do not fall back to
// browserslist defaults.
const { checkBrowsers } = require("react-dev-utils/browsersHelper");
checkBrowsers(paths.appPath, isInteractive)
	.then(() => {
		// We attempt to use the default port but if it is busy, we offer the user to
		// run on a different port. `choosePort()` Promise resolves to the next free port.
		return choosePort(HOST, DEFAULT_PORT);
	})
	.then((port) => {
		if (port == null) {
			// We have not found a port.
			return;
		}

		const config = configFactory("development");
		const protocol = process.env.HTTPS === "true" ? "https" : "http";
		const appName = require(paths.appPackageJson).name;

		const useTypeScript = fs.existsSync(paths.appTsConfig);
		const urls = prepareUrls(protocol, HOST, port, paths.publicUrlOrPath.slice(0, -1));
		// Create a webpack compiler that is configured with custom messages.
		const compiler = createCompiler({
			appName,
			config,
			urls,
			useYarn,
			useTypeScript,
			webpack,
		});
		// Load proxy config
		const proxySetting = require(paths.appPackageJson).proxy;
		const proxyConfig = prepareProxy(proxySetting, paths.appPublic, paths.publicUrlOrPath);
		// Serve webpack assets generated by the compiler over a web server.
		const serverConfig = {
			...createDevServerConfig(proxyConfig, urls.lanUrlForConfig),
			host: HOST,
			port,
		};
		const devServer = new WebpackDevServer(serverConfig, compiler);
		// Launch WebpackDevServer.
		devServer.startCallback(() => {
			if (isInteractive) {
				clearConsole();
			}

			if (env.raw.FAST_REFRESH && semver.lt(react.version, "16.10.0")) {
				console.log(chalk.yellow(`Fast Refresh requires React 16.10 or higher. You are using React ${react.version}.`));
			}

			console.log(chalk.cyan("Starting the development server...\n"));
			openBrowser(urls.localUrlForBrowser);
		});

		["SIGINT", "SIGTERM"].forEach(function (sig) {
			process.on(sig, function () {
				devServer.close();
				process.exit();
			});
		});

		if (process.env.CI !== "true") {
			// Gracefully exit when stdin ends
			process.stdin.on("end", function () {
				devServer.close();
				process.exit();
			});
		}
	})
	.catch((err) => {
		if (err && err.message) {
			console.log(err.message);
		}
		process.exit(1);
	});
